Mounting brackets having clamps with one fixed side clamp and an opposite facing moveable clamp have been used over the years to mount accessories, such as flashlights, sights and fore grips to existing picatinny rails on firearms. Many of these types of devices use rotatable screw type fasteners and/or use pivotable/foldable levers to move the move a moveable clamp portion against a fixed and stationary clamp portion so that the clamp portions clamp about exterior sides of the existing picatinny rails. However, both the screwable fasteners and the pivotable levers have problems.
Screw type fasteners for the clamp brackets often have knob head or lever head or thumb screw head which are rotated to move a moveable clamp portion toward a fixed clamp portion. See for Example, U.S. Pat. No. 3,612,462 to Mooney; U.S. Pat. No. 5,680,725 to Bell and U.S. Pat. No. 6,922,934 to Huan. However, there are problems with these types of clamp brackets.
The enlarged knob or lever head often sticks out with a high profile position and can catch and become snagged by the user. The snag can potentially loosen the screw connection by unraveling the threads of the screw by rubbing against the screw head which can result in an inadvertent release of the clamp bracket and the accessory from the firearm. Additionally, the loosened screw can eventually fall off and become lost rendering the clamp bracket useless until another screw fastener is used.
Additionally, the screw fasteners are not easy for the user to install the clamp bracket or to remove the clamp bracket. Having to continuously rotate a screw fastener can be tedious and time consuming and would not be desirable for users of the weapons that use the clamp brackets. For example, law enforcement and/or snipers in the field generally need to quickly and efficiently attach and detach their accessories such as sights, flashlights and fore grips from their weapons. Any unnecessary time delays to attach or detach such accessories to weapons can be dangerous to the user.
Pivotable/foldable levers have also been used over the years with clamp brackets that mount accessories such as flashlights, sights and fore grips to picatinny rails on firearms and/or to clamp photographic equipment such as cameras to stands. A user will generally pivot or fold the levers to move a moveable clamp portion toward a fixed clamp portion. See for example, U.S. Pat. No. 6,773,172 to Johnson et al.; U.S. Pat. No. 7,272,904 to Larue; U.S. Pat. No. 7,823,316 to Storch; D637,260 to Swan; and U.S. Pat. No. 8,112,933 to Swan and U.S. Published Patent Application 2011/0076095 to Storch et al. However, there are problems with these types of clamp brackets.
Many of the pivotable/foldable levers have the tips or free ends that can stick out up to being perpendicular from the sides of the clamp brackets when the bracket is in a closed position. Even with a low profile positioned lever, the levers can snag which can result in an inadvertent release of the clamp bracket and the accessory from the firearm.
Attempts over the years have been made to prevent the snag issue from causing an inadvertent release, such as those shown and described by Storch '095 and Swan '933.
Storch '095 requires a separate lock that must be disengaged so that the lever can pivot from a closed position to an open position. Extra parts such as springs and ball bearings are used to hold the lever in a locked position. Another version has a depressible button that must be separately actuated to allow the lever to move to an open position. Swan '933 has an extra spring biased depressible locking lever that must be separately actuated for preventing a main type lever from being inadvertently released.
Both Storch '095 and Swan '933 require expensive extra parts that would raise the cost of the traditional clamp bracket. Also, the more moveable parts and the greater the complexity of these clamp brackets, the greater the chance of failure that can occur over time. Additionally, both references can cause a delay of releasing the main lever which is not a desirable effect when using accessories on weapons.
Also, the most of the side edges of the main levers in both the Storch '095 and Swan '933 references are exposed in the clamp bracket lock position. An inadvertent release is still possible if exposed side edges of the lever become snagged.
An additional problem with most prior art pivotable/foldable levers and their assemblies is that most of the parts require metal materials that require machined and/or cast metal parts that can be expensive and labor intensive and cost and time.
Additionally, the exposure of the sides and tip ends of the pivotable/foldable levers having exposed levers in closed positions can have other problems. Dropping the clamp bracket on the lever portion, and/or having an object strike against the lever portion of the clamp bracket can result in damage to the clamp bracket overtime, which can require costly and time consuming repairs or full replacement of the clamp bracket. Thus, the need exists for solutions to the above problems with the prior art.